Down syndrome cell adhesion molecule-like protein 1 (DscamL) is a cell adhesion molecule that plays a role in neuronal self-avoidance. It promotes repulsion between specific neuronal processes of either the same cell or the same subtype of cells. DscamL mediates both isoneuronal self-avoidance for creating an orderly neurite arborization in retinal rod bipolar cells and heteroneuronal self-avoidance to maintain mosaic spacing between aII amacrine cells. DscamL has been detected in heart, liver, pancreas, skeletal muscle, kidney and brain.